monero/src/device_trezor/device_trezor_base.cpp

// Copyright (c) 2017-2018, The Monero Project
//
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// permitted provided that the following conditions are met:
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//    conditions and the following disclaimer.
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// 2. Redistributions in binary form must reproduce the above copyright notice, this list
//    of conditions and the following disclaimer in the documentation and/or other
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#include "device_trezor_base.hpp"
#include <boost/algorithm/string/classification.hpp>
#include <boost/algorithm/string/split.hpp>
#include <boost/regex.hpp>

namespace hw {
namespace trezor {

#ifdef WITH_DEVICE_TREZOR

#undef MONERO_DEFAULT_LOG_CATEGORY
#define MONERO_DEFAULT_LOG_CATEGORY "device.trezor"
#define TREZOR_BIP44_HARDENED_ZERO 0x80000000

    const uint32_t device_trezor_base::DEFAULT_BIP44_PATH[] = {0x8000002c, 0x80000080};

    device_trezor_base::device_trezor_base(): m_callback(nullptr) {

    }

    device_trezor_base::~device_trezor_base() {
      try {
        disconnect();
        release();
      } catch(std::exception const& e){
        MERROR("Could not disconnect and release: " << e.what());
      }
    }

    /* ======================================================================= */
    /*                              SETUP/TEARDOWN                             */
    /* ======================================================================= */

    bool device_trezor_base::reset() {
      return false;
    }

    bool device_trezor_base::set_name(const std::string & name) {
      this->m_full_name = name;
      this->name = "";

      auto delim = name.find(':');
      if (delim != std::string::npos && delim + 1 < name.length()) {
        this->name = name.substr(delim + 1);
      }

      return true;
    }

    const std::string device_trezor_base::get_name() const {
      if (this->m_full_name.empty()) {
        return std::string("<disconnected:").append(this->name).append(">");
      }
      return this->m_full_name;
    }

    bool device_trezor_base::init() {
      if (!release()){
        MERROR("Release failed");
        return false;
      }

      return true;
    }

    bool device_trezor_base::release() {
      try {
        disconnect();
        return true;

      } catch(std::exception const& e){
        MERROR("Release exception: " << e.what());
        return false;
      }
    }

    bool device_trezor_base::connect() {
      disconnect();

      // Enumerate all available devices
      try {
        hw::trezor::t_transport_vect trans;

        MDEBUG("Enumerating Trezor devices...");
        enumerate(trans);

        MDEBUG("Enumeration yielded " << trans.size() << " devices");
        for (auto &cur : trans) {
          MDEBUG("  device: " << *(cur.get()));
          std::string cur_path = cur->get_path();
          if (boost::starts_with(cur_path, this->name)) {
            MDEBUG("Device Match: " << cur_path);
            m_transport = cur;
            break;
          }
        }

        if (!m_transport) {
          MERROR("No matching Trezor device found. Device specifier: \"" + this->name + "\"");
          return false;
        }

        m_transport->open();
        return true;

      } catch(std::exception const& e){
        MERROR("Open exception: " << e.what());
        return false;
      }
    }

    bool device_trezor_base::disconnect() {
      m_device_state.clear();
      m_features.reset();

      if (m_transport){
        try {
          m_transport->close();
          m_transport = nullptr;

        } catch(std::exception const& e){
          MERROR("Disconnect exception: " << e.what());
          m_transport = nullptr;
          return false;
        }
      }
      return true;
    }

    /* ======================================================================= */
    /*  LOCKER                                                                 */
    /* ======================================================================= */

    //lock the device for a long sequence
    void device_trezor_base::lock() {
      MTRACE("Ask for LOCKING for device " << this->name << " in thread ");
      device_locker.lock();
      MTRACE("Device " << this->name << " LOCKed");
    }

    //lock the device for a long sequence
    bool device_trezor_base::try_lock() {
      MTRACE("Ask for LOCKING(try) for device " << this->name << " in thread ");
      bool r = device_locker.try_lock();
      if (r) {
        MTRACE("Device " << this->name << " LOCKed(try)");
      } else {
        MDEBUG("Device " << this->name << " not LOCKed(try)");
      }
      return r;
    }

    //unlock the device
    void device_trezor_base::unlock() {
      MTRACE("Ask for UNLOCKING for device " << this->name << " in thread ");
      device_locker.unlock();
      MTRACE("Device " << this->name << " UNLOCKed");
    }

    /* ======================================================================= */
    /*  Helpers                                                                */
    /* ======================================================================= */

    void device_trezor_base::require_connected(){
      if (!m_transport){
        throw exc::NotConnectedException();
      }
    }

    void device_trezor_base::require_initialized(){
      if (!m_features){
        throw exc::TrezorException("Device state not initialized");
      }

      if (m_features->has_bootloader_mode() && m_features->bootloader_mode()){
        throw exc::TrezorException("Device is in the bootloader mode");
      }

      if (m_features->has_firmware_present() && !m_features->firmware_present()){
        throw exc::TrezorException("Device has no firmware loaded");
      }

      // Hard requirement on initialized field, has to be there.
      if (!m_features->has_initialized() || !m_features->initialized()){
        throw exc::TrezorException("Device is not initialized");
      }
    }

    void device_trezor_base::call_ping_unsafe(){
      auto pingMsg = std::make_shared<messages::management::Ping>();
      pingMsg->set_message("PING");

      auto success = this->client_exchange<messages::common::Success>(pingMsg);  // messages::MessageType_Success
      MDEBUG("Ping response " << success->message());
      (void)success;
    }

    void device_trezor_base::test_ping(){
      require_connected();

      try {
        this->call_ping_unsafe();

      } catch(exc::TrezorException const& e){
        MINFO("Trezor does not respond: " << e.what());
        throw exc::DeviceNotResponsiveException(std::string("Trezor not responding: ") + e.what());
      }
    }

    void device_trezor_base::write_raw(const google::protobuf::Message * msg){
      require_connected();
      CHECK_AND_ASSERT_THROW_MES(msg, "Empty message");
      this->get_transport()->write(*msg);
    }

    GenericMessage device_trezor_base::read_raw(){
      require_connected();
      std::shared_ptr<google::protobuf::Message> msg_resp;
      hw::trezor::messages::MessageType msg_resp_type;

      this->get_transport()->read(msg_resp, &msg_resp_type);
      return GenericMessage(msg_resp_type, msg_resp);
    }

    GenericMessage device_trezor_base::call_raw(const google::protobuf::Message * msg) {
      write_raw(msg);
      return read_raw();
    }

    bool device_trezor_base::message_handler(GenericMessage & input){
      // Later if needed this generic message handler can be replaced by a pointer to
      // a protocol message handler which by default points to the device class which implements
      // the default handler.
      switch(input.m_type){
        case messages::MessageType_ButtonRequest:
          on_button_request(input, dynamic_cast<const messages::common::ButtonRequest*>(input.m_msg.get()));
          return true;
        case messages::MessageType_PassphraseRequest:
          on_passphrase_request(input, dynamic_cast<const messages::common::PassphraseRequest*>(input.m_msg.get()));
          return true;
        case messages::MessageType_PassphraseStateRequest:
          on_passphrase_state_request(input, dynamic_cast<const messages::common::PassphraseStateRequest*>(input.m_msg.get()));
          return true;
        case messages::MessageType_PinMatrixRequest:
          on_pin_request(input, dynamic_cast<const messages::common::PinMatrixRequest*>(input.m_msg.get()));
          return true;
        default:
          return false;
      }
    }

    void device_trezor_base::ensure_derivation_path() noexcept {
      if (m_wallet_deriv_path.empty()){
        m_wallet_deriv_path.push_back(TREZOR_BIP44_HARDENED_ZERO);  // default 0'
      }
    }

    void device_trezor_base::set_derivation_path(const std::string &deriv_path){
      this->m_wallet_deriv_path.clear();

      if (deriv_path.empty() || deriv_path == "-"){
        ensure_derivation_path();
        return;
      }

      CHECK_AND_ASSERT_THROW_MES(deriv_path.size() <= 255, "Derivation path is too long");

      std::vector<std::string> fields;
      boost::split(fields, deriv_path, boost::is_any_of("/"));
      CHECK_AND_ASSERT_THROW_MES(fields.size() <= 10, "Derivation path is too long");

      boost::regex rgx("^([0-9]+)'?$");
      boost::cmatch match;

      this->m_wallet_deriv_path.reserve(fields.size());
      for(const std::string & cur : fields){
        const bool ok = boost::regex_match(cur.c_str(), match, rgx);
        CHECK_AND_ASSERT_THROW_MES(ok, "Invalid wallet code: " << deriv_path << ". Invalid path element: " << cur);
        CHECK_AND_ASSERT_THROW_MES(match[0].length() > 0, "Invalid wallet code: " << deriv_path << ". Invalid path element: " << cur);

        const unsigned long cidx = std::stoul(match[0].str()) | TREZOR_BIP44_HARDENED_ZERO;
        this->m_wallet_deriv_path.push_back((unsigned int)cidx);
      }
    }

    /* ======================================================================= */
    /*                              TREZOR PROTOCOL                            */
    /* ======================================================================= */

    bool device_trezor_base::ping() {
      AUTO_LOCK_CMD();
      if (!m_transport){
        MINFO("Ping failed, device not connected");
        return false;
      }

      try {
        this->call_ping_unsafe();
        return true;

      } catch(std::exception const& e) {
        MERROR("Ping failed, exception thrown " << e.what());
      } catch(...){
        MERROR("Ping failed, general exception thrown" << boost::current_exception_diagnostic_information());
      }

      return false;
    }

    void device_trezor_base::device_state_reset_unsafe()
    {
      require_connected();
      auto initMsg = std::make_shared<messages::management::Initialize>();

      if(!m_device_state.empty()) {
        initMsg->set_allocated_state(&m_device_state);
      }

      m_features = this->client_exchange<messages::management::Features>(initMsg);
      initMsg->release_state();
    }

    void device_trezor_base::device_state_reset()
    {
      AUTO_LOCK_CMD();
      device_state_reset_unsafe();
    }

    void device_trezor_base::on_button_request(GenericMessage & resp, const messages::common::ButtonRequest * msg)
    {
      CHECK_AND_ASSERT_THROW_MES(msg, "Empty message");
      MDEBUG("on_button_request, code: " << msg->code());

      messages::common::ButtonAck ack;
      write_raw(&ack);

      if (m_callback){
        m_callback->on_button_request();
      }

      resp = read_raw();
    }

    void device_trezor_base::on_pin_request(GenericMessage & resp, const messages::common::PinMatrixRequest * msg)
    {
      MDEBUG("on_pin_request");
      CHECK_AND_ASSERT_THROW_MES(msg, "Empty message");

      epee::wipeable_string pin;

      if (m_callback){
        m_callback->on_pin_request(pin);
      }

      // TODO: remove PIN from memory
      messages::common::PinMatrixAck m;
      m.set_pin(pin.data(), pin.size());
      resp = call_raw(&m);
    }

    void device_trezor_base::on_passphrase_request(GenericMessage & resp, const messages::common::PassphraseRequest * msg)
    {
      CHECK_AND_ASSERT_THROW_MES(msg, "Empty message");
      MDEBUG("on_passhprase_request, on device: " << msg->on_device());
      epee::wipeable_string passphrase;

      if (m_callback){
        m_callback->on_passphrase_request(msg->on_device(), passphrase);
      }

      messages::common::PassphraseAck m;
      if (!msg->on_device()){
        // TODO: remove passphrase from memory
        m.set_passphrase(passphrase.data(), passphrase.size());
      }

      if (!m_device_state.empty()){
        m.set_allocated_state(&m_device_state);
      }

      resp = call_raw(&m);
      m.release_state();
    }

    void device_trezor_base::on_passphrase_state_request(GenericMessage & resp, const messages::common::PassphraseStateRequest * msg)
    {
      MDEBUG("on_passhprase_state_request");
      CHECK_AND_ASSERT_THROW_MES(msg, "Empty message");

      m_device_state = msg->state();
      messages::common::PassphraseStateAck m;
      resp = call_raw(&m);
    }

#endif //WITH_DEVICE_TREZOR
}}